linux-toradex.git/block/blk-iocost.c, branch v6.3-rc3

blk-iocost: Pass gendisk to ioc_refresh_params

2023-02-28T12:51:19+00:00

Current kernel (d2980d8d826554fa6981d621e569a453787472f8) crashes
when blk_iocost_init for `nvme1` disk.

	BUG: kernel NULL pointer dereference, address: 0000000000000050
	#PF: supervisor read access in kernel mode
	#PF: error_code(0x0000) - not-present page

	blk_iocost_init (include/asm-generic/qspinlock.h:128
			 include/linux/spinlock.h:203
			 include/linux/spinlock_api_smp.h:158
			 include/linux/spinlock.h:400
			 block/blk-iocost.c:2884)
	ioc_qos_write (block/blk-iocost.c:3198)
	? kretprobe_perf_func (kernel/trace/trace_kprobe.c:1566)
	? kernfs_fop_write_iter (include/linux/slab.h:584 fs/kernfs/file.c:311)
	? __kmem_cache_alloc_node (mm/slab.h:? mm/slub.c:3452 mm/slub.c:3491)
	? _copy_from_iter (arch/x86/include/asm/uaccess_64.h:46
			   arch/x86/include/asm/uaccess_64.h:52
			   lib/iov_iter.c:183 lib/iov_iter.c:628)
	? kretprobe_dispatcher (kernel/trace/trace_kprobe.c:1693)
	cgroup_file_write (kernel/cgroup/cgroup.c:4061)
	kernfs_fop_write_iter (fs/kernfs/file.c:334)
	vfs_write (include/linux/fs.h:1849 fs/read_write.c:491
		   fs/read_write.c:584)
	ksys_write (fs/read_write.c:637)
	do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
	entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120)

This happens because ioc_refresh_params() is being called without
a properly initialized ioc->rqos, which is happening later in the callee
side.

ioc_refresh_params() -> ioc_autop_idx() tries to access
ioc->rqos.disk->queue but ioc->rqos.disk is NULL, causing the BUG above.

Create function, called ioc_refresh_params_disk(), that is similar to
ioc_refresh_params() but where the "struct gendisk" could be passed as
an explicit argument. This function will be called when ioc->rqos.disk
is not initialized.

Fixes: ce57b558604e ("blk-rq-qos: make rq_qos_add and rq_qos_del more useful")

Signed-off-by: Breno Leitao 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230228111654.1778120-1-leitao@debian.org
Reviewed-by: Christoph Hellwig 
Signed-off-by: Jens Axboe

Revert "blk-cgroup: pin the gendisk in struct blkcg_gq"

2023-02-14T21:24:09+00:00

This reverts commit 84d7d462b16dd5f0bf7c7ca9254bf81db2c952a2.

Signed-off-by: Christoph Hellwig 
Link: https://lore.kernel.org/r/20230214183308.1658775-6-hch@lst.de
Signed-off-by: Jens Axboe

blk-cgroup: pass a gendisk to pd_alloc_fn

2023-02-03T15:20:05+00:00

No need to the request_queue here, pass a gendisk and extract the
node ids from that.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Andreas Herrmann 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230203150400.3199230-18-hch@lst.de
Signed-off-by: Jens Axboe

blk-cgroup: pass a gendisk to blkcg_{de,}activate_policy

2023-02-03T15:20:05+00:00

Prepare for storing the blkcg information in the gendisk instead of
the request_queue.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Andreas Herrmann 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230203150400.3199230-17-hch@lst.de
Signed-off-by: Jens Axboe

blk-rq-qos: store a gendisk instead of request_queue in struct rq_qos

2023-02-03T15:20:05+00:00

This is what about half of the users already want, and it's only going to
grow more.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Andreas Herrmann 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230203150400.3199230-16-hch@lst.de
Signed-off-by: Jens Axboe

blk-rq-qos: constify rq_qos_ops

2023-02-03T15:20:05+00:00

These op vectors are constant, so mark them const.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Andreas Herrmann 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230203150400.3199230-15-hch@lst.de
Signed-off-by: Jens Axboe

blk-rq-qos: make rq_qos_add and rq_qos_del more useful

2023-02-03T15:20:05+00:00

Switch to passing a gendisk, and make rq_qos_add initialize all required
fields and drop the not required q argument from rq_qos_del.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Andreas Herrmann 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230203150400.3199230-14-hch@lst.de
Signed-off-by: Jens Axboe

blk-wbt: pass a gendisk to wbt_{enable,disable}_default

2023-02-03T15:20:05+00:00

Pass a gendisk to wbt_enable_default and wbt_disable_default to
prepare for phasing out usage of the request_queue in the blk-cgroup
code.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Andreas Herrmann 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230203150400.3199230-9-hch@lst.de
Signed-off-by: Jens Axboe

blk-cgroup: pin the gendisk in struct blkcg_gq

2023-02-03T15:20:05+00:00

Currently each blkcg_gq holds a request_queue reference, which is what
is used in the policies.  But a lot of these interfaces will move over to
use a gendisk, so store a disk in struct blkcg_gq and hold a reference to
it.

Signed-off-by: Christoph Hellwig 
Reviewed-by: Andreas Herrmann 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230203150400.3199230-7-hch@lst.de
Signed-off-by: Jens Axboe

blk-iocost: change div64_u64 to DIV64_U64_ROUND_UP in ioc_refresh_params()

2023-01-29T22:18:34+00:00

vrate_min is calculated by DIV64_U64_ROUND_UP, but vrate_max is calculated
by div64_u64. Vrate_min may be 1 greater than vrate_max if the input
values min and max of cost.qos are equal.

Signed-off-by: Li Nan 
Signed-off-by: Yu Kuai 
Acked-by: Tejun Heo 
Link: https://lore.kernel.org/r/20230117070806.3857142-6-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe